The present description relates to the technical field of dual-chamber cartridges and syringes and in particular relates to an intermediate product for producing pre-filled dual-chamber syringes or cartridges and method of producing said intermediate product.
Pre-filled dual-chamber syringes or cartridges have been known for a long time and are today widely used. Said dual-chamber syringes or cartridges comprise a tubular containment body and two substances, of which at least one is a liquid substance, contained in two separate chambers defined inside the containment body.
The two substances, which are for example a solid substance and a liquid substance, are intended to be mixed one with the other immediately before injection. The liquid substance is for example a solvent for injectable use. For the mixing of the two substances the two chambers are placed in communication one with the other to reconstitute an injectable solution, for example by providing a bypass element in the pre-filled syringe or cartridge.
WO99/15215 describes, referring to FIG. 4 of this document, a method of filling a dual-chamber syringe shaped like an ampoule, wherein the filling of the two chambers takes place in a sterile chamber 40, in which are provided in sequence:
the insertion of the middle stopper in the syringe (step indicated as “MIDDLE PLUNGER CHARGING”);
the charging of the front chamber of the syringe with a solution (step indicated as “SOLUTION CHARGING”) on the side of the front opening of the syringe;
lyophilization of the abovementioned solution (step indicated as “LYOPHILIZATION”);
closure of the front opening of the syringe (step indicated as “SEALING”);
filling with the solvent (step indicated as “SOLVENT CHARGING”);
the insertion of the rear stopper in the syringe (step indicated as “REAR PLUNGER CHARGING”);
The need is felt to provide a method of filling of a dual-chamber syringe or cartridge which, compared to filling methods of the prior art, is simple and flexible in relation to the type of substances to be dosed inside the chambers of the syringe or cartridge.
A general object of the present description is that of making available an intermediate product for the production of pre-filled syringes or cartridges which allows the abovementioned need to be fulfilled.